Effect of trimethylphenylammonium tribromide/carbonaceous nanosystems on mechanical and thermal properties of unsaturated polyester resin: Experimental and computational perspective

A systematic study on the mechanical and thermal properties of unsaturated polyester resin (UPR) on adding Trimethylphenylammoniumtribromide (TMPTB), a relatively unexplored ionic system, as a modifier in combination with various carbonaceous nanosystems are described. Among the various systems [graphene (G), graphene oxide (GO) and carbon nanotube (CNT)] explored, an exceptional increase of 45 % in the tensile strength of unsaturated polyester resin (UPR) was observed with TMPTB in combination with graphene (G). A detailed computational analysis (DFT and QTAIM) revealed that a mutual bonding association between TMPTB, G and UPR was responsible for this promising result; further evidenced by TEM analysis. The increase in tensile strength was accompanied by an increase in thermal stability, Tg and storage modulus of the system, as observed in TGA and DMA studies. This work not only introduce a new class of modifier system for enhancing the mechanical strength of UPR; but also highlight the significance of computational analysis (seldom used in this area) in exploring the intramolecular forces (or factors) responsible for such observations, and thereby promoting new horizon in the upcoming research for design and development of novel modifiers for specific applications.